IAG_Ch 8_Circles

Chapter 8 Review: Circles

IAG 5th Period

Target 8.1

Recall there are two different equations that we can use when writing the equation of a circle

x² + y² = r²

We use this equation when we have our center at the origin.

Multiple Choice

Write the equation of a circle based on the graph given below.

• x² + y² = 2

• x² + y² = 4

• x² - y² = 4

• x² - y² = 2

(x-h)² + (y-k)² = r²

This equation is used when we have a center at (h, k).

Multiple Choice

Write the equation of a circle with a center at (2, 5) and radius of 4

• (x-2)² + (y-5)² = 16

• (x-2)² + (y-5)² = 4

• (x+2)² + (y+5)² = 16

• (x+2)² + (y+5)² = 4

Target 8.2

Open Ended

What is the difference between Circumference and arc length?

Open Ended

What is the difference between the area of a circle and area of a sector?

Target 8.3

Inscribed Angle Theorem: The measure of an angle inscribed in a circle is HALF the measure of its intercepted arc.

Multiple Choice

If $m\angle ABC\ =\ 40\degree$  then find the measurement of the arc  $AC$  

•  $40\degree$  

•  $20\degree$  

•  $80\degree$  

Target 4

Tangent Line: A line that intersects a circle at one point. A tangent segment is perpendiculat to the radius of circle creating a  $90\degree$ angle.

Open Ended

Explain how to find the segment OB

Theorem:

If two segments are tangent to a circle from the same external point, then the segments are congruent.

Multiple Choice

Assume both segments are tangent to the center point. Find x

• x = 5

• x = 3

• x = 4

• x = 7

Multiple Choice

Find the perimeter of the following triangle ABC.

• 44

• 43

• 37

• 34